This invention relates to corner posts used in the packaging of articles and, particularly, to corner posts applied, e.g., as vertical corner posts such as for insertion into the corners of a straight-sided flexible container adapted for cushioning the straight corners and edges of packaged articles along the full height thereof and also adapted to permit the stacking of the packaged articles on each other without damaging the container or the article contained therein, and horizontal corner posts permitting pick up and movement of packed articles by a squeeze truck without sideways crushing of the articles.
In packaging a number of articles including heavy articles such as refrigerators, television sets, stoves, air conditioners and washing machines and dryers, it is customary to package them in relatively lightweight containers formed of paperboard or corrugated or to envelop them in a plastic film such as by shrink or stretch wrap techniques. The article is located and cushioned within the container or film by corner posts which typically are one or more pieces of cardboard folded to a 90.degree. angle and inserted along the edges of the article and the corners of the containers or film. Such corner posts are used to provide cushioning to protect the corners of the packed article from damage such as scratching and denting during shipping and handling.
A number of corner posts are known to the art. Representative of such designs are U.S. Pat. Nos. 2,068,771; 2,160,221; 2,196,157; 2,514,833; 3,556,529; 3,133,687; 3,337,111; 3,536,245; 3,072,313; 3,433,354; 3,708,101; 3,734,389; 4,120,441; and G.B. 2,080,767. These prior art corner posts, however, all have one or more of the following disadvantages. Although some provide relatively good cushioning, they do not provide a load bearing capacity in the vertical direction which would permit the vertical stacking of loaded containers, or, if they do, they are of substantial bulk and thus require large amounts of materials, are heavy, and take up space. For protectors not providing vertical load bearing capacity, when stacking of such containers is attempted, the weight of the upper container crushes the underlying containers by bending or buckling the walls of the container which bear the stacking load. Others which attempt to provide such vertical load bearing capacity in turn do not always provide sufficient cushioning and/or are relatively complex in design and expensive to manufacture. Since the packaging materials do not add value to the product itself, the costs of such materials are an important consideration to the manufacturer who uses such posts in shipping finished goods. Finally, some designs are subject to crushing by lateral forces supplied to the container and by shifting movement of the article within the container detracting from the cushioning protection for the edge and corners of the article.